As a display device, TFT-LCD (Thin Film Transistor Liquid Crystal Display) has been used in high performance display field more and more because of its advantages of small size, low power consumption, free of radiation and low cost.
A TFT-LCD comprises an array substrate and a color film substrate. A liquid crystal layer is arranged between the array substrate and the color film substrate. Wherein the array substrate may comprise a plurality of crossed gate lines and data lines; a plurality of pixel units arranged in a matrix form are defined by the gate lines and data lines; and each pixel unit is provided with a pixel electrode and a TFT. A drain of the TFT is connected with the pixel unit. During display, a gate signal is input from a gate line, a line of TFTs are thus switched on; an data signal is then input from a data line, the data signal is transmitted from a source of the TFT to the drain of the TFT, charging the pixel electrode connected with the drain. An electric field is generated between the pixel electrode and the common electrode. Under the action of the electric field, the liquid crystal molecules corresponding to a position of the pixel electrode are deflected, realizing the control on light intensity; with the filtering function of the color film substrate, color image display can then be realized.
In order to simplify the production process, the pixel electrode is typically formed with a rectangular shape in the existing technology. However, in such a manner, point discharge occurs easily on the position of opposite corners between two adjacent pixel electrodes, which makes the charge distribution on the pixel electrodes is not uniform, thereby affecting the uniformity of the display image.